1. Field of the Invention
This invention relates generally to an activated carbon for odor control and methods for making same and, more particularly, to an activated carbon, metal oxide filter element to control odor in a gaseous stream and methods of making same.
2. Description of Related Art
Activated carbons have long been known for their capacity to sorb odors. Activated carbons capture substances generally through physical sorption, chemical sorption and catalytic reaction. It is well known that the presence of metals in activated carbon can enhance the efficiency and selectivity of the activated carbon in sorptive or filtering applications. Methods for producing porous structural materials containing adsorbent particles of activated carbon and metals or metal oxides are conventionally known.
Activated carbon impregnated with metals are typically formed by dispersing activated carbon powders in a solution of a metal salt. The powder is filtered out, dried, and heated to decompose the salt to the desired metal or metal oxide catalyst. Multiple impregnations are usually required to obtain the desired quantity of catalyst on the activated carbon.
Other methods of forming activated carbons are disclosed in U.S. Pat. No. 4,242,226, to Siren; U.S. Pat. No. 4,970,189 to Tachibana; in U.S. Pat. No. 5,488,023, to Gadkaree et al.; U.S. Pat. No. 5,997,829 to Sekine et al.; U.S. Pat. No. 4,482,641 to Wennerberg; U.S. Pat. No. 4,831,003 to Lang et al.; and U.S. Pat. No. 5,948,398 to Hanamoto et al.